running lean on top
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Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
Forum rules
Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
running lean on top
I have a 1996 chevy cavalier 2.4l stock engine controlled by ms1 v2.2 fuel only setup w/narrowband o2! My problem is that when the car reaches 5600 RPM, my O2s go lean, TPs acceleration spikes, duty cycle spikes and the pulse width spikes. I'm using 36 lb fuel injectors.
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David Cowie
- MegaSquirt Newbie
- Posts: 3
- Joined: Wed Nov 24, 2004 8:16 pm
- Location: Australia
Is the engine running OK at that point i.e. is it pinging or misfiring? A misfire means more oxygen in the exhaust.
Assuming its running OK, a lot depends on what the throttle and the TPS are doing - if you are getting acceleration spikes when the throttle is not moving, then you may have the TPS dot threshold too low, or a noisy TPS signal triggering the accel. enrich. It's possible for a TPS to give a good signal in one part of its travel and a bad one in another, although they usually wear out around idle, not WOT.
If you are near wide open throttle, then assuming the TPS is correctly calibrated, the TPS ADC should be high enough that the O2 correction is off, ditto for when Accel Enrich is triggered. In that case and if the engine is not misfiring, then if it's reading lean on the O2 sensor even when you've got extra fuelling from the Accel Enrich, it sounds as if the VE table needs to be upped in that area.
Perhaps post a log?
Assuming its running OK, a lot depends on what the throttle and the TPS are doing - if you are getting acceleration spikes when the throttle is not moving, then you may have the TPS dot threshold too low, or a noisy TPS signal triggering the accel. enrich. It's possible for a TPS to give a good signal in one part of its travel and a bad one in another, although they usually wear out around idle, not WOT.
If you are near wide open throttle, then assuming the TPS is correctly calibrated, the TPS ADC should be high enough that the O2 correction is off, ditto for when Accel Enrich is triggered. In that case and if the engine is not misfiring, then if it's reading lean on the O2 sensor even when you've got extra fuelling from the Accel Enrich, it sounds as if the VE table needs to be upped in that area.
Perhaps post a log?
David
Blue Mountains
Australia
Rover SD1 3.9L V8
Blue Mountains
Australia
Rover SD1 3.9L V8